Robot for transporting storage bins

ABSTRACT

A remotely operated vehicle or robot for picking up storage bins from a storage system includes a vehicle body, which includes a first section for storing vehicle driving means and a second section for receiving any storage bin stored in a storage column within the storage system, a vehicle lifting device in order to lift the storage bin into the second section, a first and a second set of vehicle rolling means allowing movement of the vehicle along a first and a second direction perpendicular to the first direction, respectively, within the storage system. The second section includes a cavity arranged centrally within the vehicle body. This cavity has at least one bin receiving opening facing towards the underlying storage columns At least one of the two sets of vehicle rolling means is arranged fully within the vehicle body.

FIELD OF INVENTION

The present invention relates to a remotely operated vehicle for pickingup storage bins from a storage system and to a storage system using theinventive vehicle.

BACKGROUND OF INVENTION

A remotely operated vehicle for picking up storage bins from a storagesystem is known. A detailed description of a relevant prior art storagesystem is given in WO 98/49075. Further, details of a prior art vehiclebeing suitable for such a storage system is disclosed in Norwegianpatent NO317366. More specifically the prior art storage systemcomprises a three dimensional storage grid containing storage bins thatare stacked on top of each other to a certain height. The storage gridis normally constructed as aluminum columns interconnected by top rails.A number of remotely operated vehicles, or robots, are arranged on thetop rails. Each vehicle is equipped with a lift for picking up,carrying, and placing bins that are stored inside the storage grid.

Such a prior art storage system art and prior art robot is illustratedin FIGS. 1 and 2, respectively. The storage system 3 comprises a robot 1which is arranged to move on dedicated supporting rails 13 and toreceive a storage bin 2 from a storage column 8 within a bin storinggrid 15. The storage system 3 includes a plurality of such robots 1 anda dedicated bin lift device 50, the latter being arranged to receive astorage bin 2 from the robot 1 at the top level of the bin storing grid15 and to convey the storage bin 2 down in a vertical direction to adelivery station 60.

However, the prior art robot 1 shown in both FIG. 1 and FIG. 2 suffersfrom several important disadvantageous during their operation. Firstly,the particular design of the robot prevents access to all off theavailable storage columns in the storage system. Furthermore, thisparticular design may cause an undesirable high torque during liftingand transportation of storage bins, thereby creating potentialinstability problems, as well as a clear limitation of the robotsmaximum handling weight. An additional disadvantage caused by the priorart robot design is the fact that only one particular bin and oneparticular bin height may be accepted for each type of robot in order toensure adequate stability. Finally, the presence of an integratedyoke/overhang in the upper part of the section receiving the storage binnecessitates an undesired speed reduction at the final stage of thelifting process performed by the yoke suspended vehicle lifting device.

SUMMARY

One or more embodiments of the present invention solve, or at leastsubstantially alleviate, the above-described disadvantages, i.e.,provide a vehicle/robot with higher stability properties, higher maximumhandling weights, a more effective use of available space duringoperation and a less time consuming lifting and transporting process ofstorage bins.

In particular, one or more embodiments of the present invention relateto a remotely operated vehicle or robot for picking up storage bins froma storage system. The inventive vehicle or robot comprises a vehiclebody, which vehicle body further comprises a first section for storingvehicle driving means and a second section for receiving any storage binstored in a storage column within the storage system, a vehicle liftingdevice which is at least indirectly connected to the vehicle body inorder to lift the storage bin into the second section, a first set ofvehicle rolling means connected to the vehicle body in order to allowmovement of the vehicle along a first direction (X) within the storagesystem during use and a second set of vehicle rolling means connected tothe vehicle body in order to allow movement of the vehicle along asecond direction (Y) in the storage system during use. The seconddirection (Y) is oriented perpendicular to the first direction (X).

The inventive vehicle is characterized in that the second sectioncomprises a cavity arranged centrally within the vehicle body. Thiscavity has at least one bin receiving opening facing towards theunderlying storage columns during use. In addition, at least one of thetwo sets of vehicle rolling means is arranged fully within the vehiclebody.

In order to allow easy entrance of the storage bin into the centralcavity, its volume should be larger than the largest storage binintended to be picked from the storage system. Likewise, the crosssectional area of at least one of the at least one bin receiving openingshould be larger than the cross sectional area of the storage bin wallsoriented parallel to the cavity opening(s).

The vehicle may further comprise means for reversibly and selectivelydisplacing either the first set of vehicle rolling means or the secondvehicle rolling means away from an underlying vehicle support within thestorage system during a change of vehicle direction between the firstdirection (X) and the second direction (Y).

Furthermore, in an embodiment the first section may be arranged relativeto the second section in such a way that the cross section of thevehicle parallel to the underlying vehicle support deviates from aquadratic shape.

In a preferred embodiment the vehicle body covers less or equal to thelateral cross sectional area of one central storage column in the firstdirection (X) and covers the lateral cross sectional area of more thanone central storage column in the second direction (Y) during use. In amore specific example the vehicle body extends beyond the lateral crosssectional area of the central storage column at both sides facing thesecond direction (Y), i.e. covering also some of the cross sectionalareas of the adjacent storage columns extending in the second direction(Y). The degree of extension from the central storage column ispreferably equal on both of these sides. Central storage column isdefined as the storage column which is immediately below a robot whenthe latter has reached a position allowing pick-up of a storage bin.

In order to inter alia allow high vehicle stability both sets of vehiclerolling means is preferably arranged symmetrically around the cavity,for example near the lower corners of the vehicle. At least one, andmost preferably both, set(s) of vehicle rolling means may comprise atleast four wheels. Other embodiments such as the use two perpendicularoriented caterpillar belts may be envisaged. Furthermore, both sets havean exterior design matching a corresponding exterior design onsupporting rails constituting the vehicle support in order to provideincreased lateral stability when interconnected. Such supporting railswould be arranged in a two dimensional matrix on top of a bin storingstructure or grid, where the principal directions of both the matrix andthe grid are congruent with the vehicle's first direction (X) and seconddirection (Y).

The vehicle may advantageously also include position sensing means toallow measurements of the vehicle position within the storage systemduring use. This position sensing means may comprise a plurality ofposition sensors arranged in at least some of the positions on thevehicle body which would transverse the locations of vehicle supportwhere the supporting rails are crossing, for example underneath thevehicle, close to its lower corners.

One or more embodiments of the present invention also relate to astorage system which comprises a remotely operated vehicle in accordancewith the above mentioned features, a vehicle support comprising aplurality of supporting rails forming a two dimensional matrix ofguiding meshes, wherein the vehicle support is configured to guide themovements of the vehicle in the first direction (X) and the seconddirection (Y) during use, a bin storing structure or grid supporting thevehicle support comprising a plurality of storage columns, wherein eachof the storage columns is arranged to accommodate a vertical stack ofstorage bins and wherein the main part of the bin storing structurecoincides with positions on the vehicle support where the supportingrails are crossing, and a bin lift device arranged to convey a vehicledelivered storage bin in a direction perpendicular to the lateral planeof the vehicle support between the vehicle support and a deliverystation.

In a preferred embodiment at least some of the supporting rails arrangedat the outer lateral border areas of the vehicle support form outerguiding meshes having reduced average cross sectional areas compared tothe average cross sectional area of the remaining guiding meshes in thevehicle support. For example, the average reduced cross sectional areasof the outer guiding meshes may be about half of the average crosssectional area of the remaining guiding meshes in the vehicle support.In a particularly preferred embodiment these cross sectional areas ofthe outer guiding meshes are reduced only along the second direction (Y)of the vehicle support.

The central arrangement of the cavity in the vehicle body relative tothe second direction (Y) effectively remove the undesired torque,thereby improving the stability of the robot or vehicle. Thisarrangement also results in a lifting and transporting process having aweight distribution with a high degree of symmetry. Furthermore, thenovel design allows the same vehicle to be used for lifting andtransporting storage bins of heights significantly less than the cavityheight (i.e. the height extending from the suspension points of thelifting device and to the lower edge of the vehicle) since theframework/body surrounding at least part of the bin receiving cavityeffectively hinders any undesired bin reeling/wobbling. The presence ofthe cavity surrounding body also allows maintaining full or nearly fulllifting speed almost all the way to its end position within the cavity,as well as initiation of stable bin transportations towards the deliverystation prior to a fully completed bin lifting from a storage column.The protective body around the cavity also gives the possibility ofstarting a descent of the lifting device event prior to the time thevehicle has come to a final halt above the storage column in question. Asignificantly higher stability and time efficiency is thus achieved.

By arranging at least one set of vehicle rolling means fully within thevehicle or robot body additional stability is obtained during thelifting process since the rolling means is situated closer to thestorage bin to be lifted. Of the same reason this arrangement reducesthe total load on the lifting device. Furthermore, the arrangement ismore space efficient relative to the prior art robot illustrated in FIG.2 since the roller means does not give any additional extensions in atleast one of the two robots moving directions (X and Y). Production ofsmaller sized robots/vehicles is also rendered possible.

These and other characteristics of the invention will be clear from thefollowing description of embodiments of the present invention, given asa non-restrictive examples, with reference to the attached drawingswherein:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a prior art storage system;

FIG. 2 is a sectional view of a prior art robot or vehicle forming partof a storage system as illustrated in FIG. 1;

FIG. 3 is a perspective base view of a remotely operated vehicleaccording to the present invention;

FIG. 4 is a perspective top view of a remotely operated vehicleaccording to the present invention;

FIG. 5 is a perspective top view of a robot assembly comprising aremotely operated vehicle according to the present invention, a storagebin and a fully enclosing cover,

FIG. 6 is a perspective top view of a bin storing grid and a vehiclesupport in accordance with the present invention;

FIG. 7 is a perspective side view of a bin storing grid and a vehiclesupport in accordance with the present invention;

FIG. 8 is a perspective side view of part of a storage system inaccordance with the present invention including a bin storing grid, avehicle support and a remotely operated vehicle; and

FIG. 9 is a schematic top view of a remotely operated vehicle moving ona two dimensional matrix of supporting rails.

DETAILED DESCRIPTION

FIG. 1 is a schematic, partly cut perspective view of a storage systemaccording to the prior art, and FIG. 2 is a sectional view of acorresponding prior art robot. Both figures have already been referredto earlier in the text. FIGS. 3 and 4 gives a perspective view in twodifferent angles of the inventive robot 1 comprising a rectangularvehicle body or framework 4 with a cavity 7 centrally arranged withinthe body 4, a top lid 72 covering the top part of the body 4, a firstset of four wheels 10 mounted inside the cavity 7 and in parallel to theinterior walls of the body 4 and a second set of four wheels 11 mountedin parallel to the exterior walls of the body 4. The first and secondset of wheels 10,11 are oriented perpendicular to each other. Further,the vehicle body 4 also includes side parts 5,5 a,5 b arranged on bothsides of the cavity 7 along at least one of the robots 1 direction ofmovements. For the sake of clarity a Cartesian coordinate system isshown with its X, Y and Z axes aligned along the principal directions ofthe rectangular vehicle body 4. The size of the cavity 7 is adapted tocontain necessary component for a lifting device 9 and to at leastcompletely contain the largest storage bin 2 intended to be picked up bythe robot 1.

FIG. 5 gives a perspective view of a robot assembly where the body 4 iscompletely covered by an enclosing cover 73 comprising handles 74 andtransmission means/control panel 75. The design of the enclosing cover73 is adapted to the particular shape given by the body 4 and theprotruding wheels 10. FIG. 5 also shows a small part of a storage bin 2arranged fully inside the cavity 7 and a small part of the liftingdevice 9. The latter is preferably composed of inter alia fourvertically moveable metal bands suspended on the cavity facing side ofthe top lid 72 in their upper ends and steering rods at the lower endscapable of being steered and fastened into adapted cavities/areas in thestorage bin 2 to be picked.

The structural principles of a grid assembly comprising a bin storingstructure or grid 15, integrated supporting rails 13 constituting thevehicle support 14 and a grid supporting base 76 are illustrated inFIGS. 6 and 7. The grid 15 comprises a plurality of pillars beingarranged with internal distances adapted to accommodate storage bins 2to be stored in stacks inside the grid 15. The rectangular arrangementsof four adjacent pillars therefore constitute a storage column 8 Boththe pillars and the rails 13 may be made of Aluminum. As for FIGS. 3 and4 a Cartesian coordinate system is shown aligned along the principaldirections of the grid assembly to ease the understanding. Thesupporting rails 13 form a two dimensional matrix of rectangular meshes,and the cross sectional area of most of these meshes coincide with thecross sectional area of each storage columns 8 set up by the underlyinggrid 15. The meshes at the border area 17,18 of the vehicle support 14(at both sides in direction Y) is illustrated with cross sectional areassmaller than the remaining meshes. The size of the border meshes 17,18should preferably be adapted to the degree of extension beyond a centralstorage column 8 a situated immediately below the cavity 7 of the robot1 when the latter is in a position for initiating pick up of a storagebin 2 contained in the central storage column 8 a (see FIGS. 8 and 9).In this way the robot 1 may reach all the storage columns 8 in thestorage system 3, i.e. independently of the robot orientation in the Ydirection. For example, if the robot 1 extends exactly over the crosssectional area of one central storage column 8 a in the X direction andover ½ of the cross sectional area of the adjacent storage column 8 b inthe Y direction, the cross sectional area of the meshes 17,18 at theborder area in the Y direction should be approximately ½ of the crosssectional area of the remaining meshes. The primary function of theseborder meshes 17,18 is thus to allow sufficient space for the robot 1having the novel design.

FIG. 8 shows the robot 1 in a lifting position above the central storagecolumn 8 a adjacent to the border area 17,18 of the grid assembly. Thevehicle lifting device 9 is in this embodiment lowered a distance intothe central storage column 8 a in order to hook onto and lift up theunderlying storage bin 2. As seen in the exemplary situation in FIGS. 8the robot 1, having the body 4 extended in the Y direction compared tothe X direction, may be driven all the way to the edge of the grid 15when the border area is designed with additional border meshes 17,18with a Y directional width approximately ½ of the Y directional widthsof the remaining meshes in the grid 15.

To better illustrate the movement of the robot 1 on the supporting rails13 constituting the vehicle support 14 some exemplary positions ofrobots 1 on a grid assembly is illustrated in FIG. 9. The thick arrowsdrawn in the centre of the robots 1 indicate allowed moving directions.When the robot 1 is situated with its cavity 7 exactly above a centralstorage column 8 a, as is the case for the top left and mid centeredrobot 1, the arrangement of the supporting rails 13 allow movement inboth X and Y directions. Any other positions on the grid assemblyrestrict the robot's 1 movement on the vehicle support 14 either in Xdirection (lower right robot 1) or in Y direction (top centered andbottom left robot 1). To allow determination of the robot position it isconsidered advantageous to equip each robot 1 with one or more positionsensors 16, for example optical sensors. Such sensors should 16preferably be mounted in one or more areas of the robot 1 which ensuresthat the sensors 16 have both non-obstructed view to the underlyingsupporting rails 13 and that they pass directly above or close to thepositions on the vehicle support 14 in which the rails 13 are crossing.The readings from the sensors 16 may inter alia dictate the furthermovement of the robot 1 and/or the operation of the vehicle liftingdevice 9.

All operations of the robot 1 are controlled by wireless communicationmeans 75 and remote control units. This includes control of the robotmovement, the vehicle lifting device and the position measurements.

In the preceding description, various aspects of the invention have beendescribed with reference to the illustrative embodiments. For purposesof explanation, specific numbers, systems and configurations were setforth in order to provide a thorough understanding of the apparatus andits workings. However, this description is not intended to be construedin a limiting sense. Various modifications and variations of theillustrative embodiment, as well as other embodiments of the apparatus,which are apparent to persons skilled in the art to which the disclosedsubject matter pertains, are deemed to lie within the scope of thepresent invention.

LIST OF REFERENCE NUMERALS/LETTERS

-   1 Remotely operated vehicle/robot-   2 Storage bin-   3 Storage system-   4 Vehicle body/framework-   5 First section (of vehicle body)/component section/side parts-   5 a First section, left-   5 b First section, right-   6 Vehicle driving means/motor unit-   7 Vehicle storage space/second part/cavity/centrally arranged cavity-   8 Storage column-   8 a Central storage column-   8 b Adjacent storage column-   9 Vehicle lifting device-   10 First set of vehicle rolling means/First set of wheels-   11 Second set of vehicle rolling means/Second set of wheels-   12 Bin receiving opening-   13 Supporting rail-   14 Vehicle support-   15 Bin storing structure/grid-   16 Position sensing means/position sensor-   17 Left outer lateral border area of vehicle support/left border    mesh-   18 Right outer lateral border area of vehicle support/right border    mesh-   50 Bin lift device-   60 Delivery station/port-   70 Yoke/overhang-   72 Top lid-   73 Enclosing cover-   74 Handles-   75 Transmission means/control panel/wireless communication means-   76 Grid supporting base

1. A remotely operated vehicle for picking up storage bins from astorage system, comprising: a vehicle body comprising a first sectionfor storing vehicle driving means and a second section for receiving anystorage bin stored in a storage column within the storage system, thesecond section comprising a centrally arranged cavity within the vehiclebody, the cavity having at least one bin receiving opening facingtowards the storage columns during use, a vehicle lifting device atleast indirectly connected to the vehicle body for lifting the storagebin into the second section; and a first set of vehicle rolling meansconnected to the vehicle body allowing movement of the vehicle along afirst direction (X) within the storage system during use, wherein thevehicle further comprises a second set of vehicle rolling meansconnected to the vehicle body allowing movement of the vehicle along asecond direction (Y) in the storage system during use, the seconddirection being perpendicular to the first direction (X), wherein atleast one of the sets of vehicle rolling means is mounted onto the innerwall of the cavity.
 2. The remotely operated vehicle according to claim1, wherein the vehicle further comprises means for reversibly andselectively displacing either the first set of vehicle rolling means orthe second vehicle rolling means away from an underlying vehicle supportwithin the storage system during a change of vehicle direction betweenthe first direction (X) and the second direction (Y).
 3. The remotelyoperated vehicle according to claim 1, wherein the vehicle body, whenoperated on the storage system comprising a plurality of storagecolumns, covers at most the lateral cross section of one central storagecolumn in the first direction (X) and covers the lateral cross sectionof more than one central storage column in the second direction (Y). 4.The remotely operated vehicle according to claim 3, wherein the vehiclebody extends beyond the lateral cross section of the central storagecolumn at both sides in the second direction (Y).
 5. The remotelyoperated vehicle according to claim 4, wherein the extension beyond thelateral cross section of the central storage column is equal on bothsides in the second direction (Y).
 6. The remotely operated vehicleaccording to claim 1, wherein both sets of vehicle rolling means aresymmetrically distributed around the centrally arranged cavity.
 7. Theremotely operated vehicle according to claim 1, wherein at least one setof vehicle rolling means comprises at least four wheels.
 8. The remotelyoperated vehicle according to claim 1, wherein, when operated on thestorage system comprising a plurality of supporting rails forming a twodimensional matrix of guiding meshes arranged on top of a bin storingstructure, both sets of vehicle rolling means aligned in the firstdirection (X) and the second direction (Y), respectively, have anexterior design that is congruent with the matrix and the bin storingstructure in order to provide increased lateral stability wheninterconnected.
 9. The remotely operated vehicle according to claim 1,wherein the vehicle comprises position sensing means to allowmeasurements of the vehicle position within the storage system duringuse.
 10. The remotely operated vehicle according to claim 9, wherein theposition sensing means comprises comprising a plurality of sensorsarranged in at least some of the positions on the vehicle body which,during use, transverse the positions of vehicle support where thesupporting rails are crossing.
 11. A storage system comprising: theremotely operated vehicle according to claim 1; a vehicle supportcomprising a plurality of supporting rails forming a two dimensionalmatrix of guiding meshes, the vehicle support being configured to guidethe movements of the vehicle in the first direction (X) and the seconddirection (Y) during use; a bin storing structure supporting the vehiclesupport, the structure comprising a plurality of storage columns,wherein: each storage column columns is arranged to accommodate avertical stack of storage bins, the main part of the bin storingstructure coincides with positions on the vehicle support where thesupporting rails are crossing; and a bin lift device arranged to conveya vehicle delivered storage bin in a direction perpendicular to thelateral plane of the vehicle support between the vehicle support and adelivery station.
 12. The storage system according to claim 11, whereinat least some of the supporting rails arranged at the outer lateralborder areas of the vehicle support form outer guiding meshes havingreduced average cross section compared to the average cross section ofthe remaining guiding meshes in the vehicle support.
 13. The storagesystem according to claim 12, wherein the average reduced cross sectionof the outer guiding meshes are about half of the average cross sectionof the remaining guiding meshes in the vehicle support.
 14. The storagesystem according to claim 12, wherein the size of the outer guiding meshis reduced only along the second direction (Y) of the vehicle support.15. The remotely operated vehicle according to claim 1, wherein thevehicle rolling means is mounted in parallel to the interior walls ofthe body.